1 Police were at the scene quickly but officers played down suggestions that Madeleine had been abducted and believed she had just wandered off. The crime scene in and around the hotel was not taped off, ruining prospects of obtaining vital forensic evidence.

2 There was a lack of specialist fingertip searching in streets around the hotel meaning more opportunities to find forensic evidence were lost. A former senior British detective working for the media called the scene "the worst preserved" he had witnessed in his career.

3 Officers failed to make early house-to-house inquiries when potential witnesses were still likely to be in the resort. Only on the Saturday, more than 48 hours later, did they start searching some local apartments and a full list of guests was obtained on Sunday. Staff at Mark Warner's complex were only questioned 60 hours after Madeleine disappeared.

4 There are still people in the same apartment block as Mr and Mrs McCann who have never been questioned. Empty properties yards from where the child was taken have never been searched.

5 Police failed to inform Spanish border authorities of Madeleine's disappearance until the morning after she was taken - giving the abductor the chance to flee the country.

6 CCTV on the main road out of Praia da Luz, going towards Spain, was not checked by police.

7 Early witness descriptions created confusion. At one stage there were six different E-fit images being shown to local people.

8 On the morning of May 7, Gerry and Kate McCann issued a televised appeal direct to the abductor. Six hours later, a police chief said at a press conference: "We are not 100 per cent certain she was abducted."

9 Detectives could not issue information on the investigation due to strict Portuguese laws on "judicial secrecy". However the law includes two exceptions, both of which apply in the case of Madeleine.

10 It meant no direct appeal for help was made and police failed to give a clear description of Madeleine. There were no posters put up in the early days. It was left to Madeleine's parents to describe what she as wearing on the night she disappeared.

11 An appeal for a suspect was finally issued 22 days after Madeleine went missing, together with a description. However police made another blunder by issuing two different height descriptions - the result of a mistranslation.

12 On May 9 the search was scaled down \u2026 searches were not very visible, helicopter not used much.

13 There was a delay in calling in specialists. Two British child abduction experts were flown in a week later, mobile phone tracker technicians who helped in the Soham investigation came in last week.

14 Leaks have hampered the inquiry. On May 16, Portuguese newspapers reported that police were "on the trail" of a Russian friend of Robert Murat, the formal suspect in the case. He was only detained for questioning after he had been traced by journalists.

15 Madeleine's favourite toy could have been a crucial key in tracking her down. She took it to bed with her every night including the night she was taken. The abductor could have left some trace of DNA evidence on it, but police did not check and Mrs McCann has had the pink soft toy with her ever since. One specialist said scientists would have needed to examine it for at least several days. He said: "Now it's probably too late. It's an absolute glaring error."